Cutting die assembly with replaceable blades

ABSTRACT

A cutting die assembly comprised of male and female die structures each being of multi-piece construction including a rigid mounting base and cutting blades together with means for convenient disassembly for replacement of the cutting blades which have suffered damage or excessive wear, thereby permitting reuse, rather than disposal, of each mounting base.

United States Patent [191 Cross CUTTING DIE ASSEMBLY WITH REPLACEABLEBLADES [76] Inventor: Tallyrand Cross, 4605 Farm Valley Road, Medford,Oreg. 97501 [22] Filed: Aug. 31, 1971 [2]] Appl. No.: 176,537

[52] U.S. Cl. 144/197, 83/685, 83/698,

76/107 C, 29/526 [51] Int. Cl B27m l/04 [58] Field of Search 76/107;146/203;

[56] References Cited UNITED STATES PATENTS 2,495,221 1/1950 Berlin76/107 C 11 3,733,462 1 June 12, 1973 3,263,549 8/1966 Jordan et al.83/698 3,335,628 8/1967 Simms et a] 76/107 C FOREIGN PATENTS ORAPPLICATIONS 776,369 6/1957 Great Britain 76/107 C PrimaryExaminerAndrew R. Juhasz Assistant Examiner-W. D. Bray Attorney-ClarenceA. OBrien and Harvey B. Jacobson [57] ABSTRACT A cutting die assemblycomprised of male and female die structures each being of multi-piececonstruction including a rigid mounting base and cutting blades togetherwith means for convenient disassembly for replacement of the cuttingblades which have suffered damage or excessive wear, thereby permittingreuse, rather than disposal, of each mounting base.

8 Claims, 5 Drawing Figures PAIENTEU Y 2 I973 SHEET 2 UP 2 Fig.3

Tal/ymno Cross CUTTING DIE ASSEMBLY WITH REPLACEABLE BLADES The presentinvention is generally related to cutting dies and, more particularly,to plywood patching machine dies, and the like.

In the past, a variety of plywood patching machine dies have beenavailable. However, these dies have been of single-piece constructionand of relatively short life, requiring frequent replacement upon wearof the cutting blades. Such replacement was costly due to the fact thatthe mounting base as well as the cutting blades were included in theone-piece construction. While this throw-away concept may be of someconvenience, it becomes extremely costly for manufacturers using suchdies in great numbers or on a continuous basis.

It is an object of the present invention to provide a novel multi-piecepatching die construction which permits easy removal of the cuttingblades from a mounting base for sharpening or replacement thereof,thereby reducing the over-all operating cost of the patching diesprocedure.

Another object of the present invention is to provide a versatilepatching die comprising a rigid mounting base and a pair of removablecurved cutting blades fastened thereto by bolts and dowels which assuresecure fastening and proper alignment upon reassembly.

It is a further object of the present invention to provide a uniquemulti-piece patching die assembly which permits convenient removal ofthe cutting blades for repair or replacement, yet, is relatively simplein overall construction, durable, long lasting, and relativelyinexpensive to manufacture.

These together with other objects and advantages which will becomesubsequently apparent reside in the details of construction andoperation as more fully hereinafter described and claimed, referencebeing had to the accompanying drawings forming a part hereof, whereinlike numerals refer to like parts throughout, and in which:

FIG. 1 is a perspective view of the female die structure associated withthe present invention;

FIG. 2 is an exploded perspective view of the female die structure shownin FIG. 1;

FIG. 3 is an exploded perspective view of the male die structure shownin FIG. 3;

FIG. 4 is a perspective view of the male die structure associated withthe present invention; and

FIG. 5 is a sectional view of the die assembly of the present inventionwith the male and female die structures mated together.

Referring now, more particularly, to FIGS. 1 and 2, the femalediestructure associated with the present invention is generallyindicated by the numeral and includes a generally rectangular rigidmounting base 12 adapted to be mounted to a conventional plywoodpatching machine, or similar equipment. Mounting base 12 is providedwith a centrally located, arcuatelyformed opening adapted to receive acorrespondingly shaped pair of male cutting blades as hereinafterexthreadedly received in mounting holes 22 formed in mounting base 12and mounting apertures 24 formed in each cutting blade.

The lower surface 26 of mounting base 12 is substantially flat in shapeand is adapted to snugly engage the upper mounting edge portions 28 and30 associated with cutting blades 16 and 18, respectively. In addition,two pairs of alignment dowels 32 and 34 extend between mounting base 12and mounting edge portions 28 and 30 of the cutting blades to assureproper alignment during reassembly. Each cutting blade is provided witha beveled edge cutting portion 36 which slopes upwardly and outwardlyfrom the bottommost edges of each cutting blade to define a curvedcutting edge.

Cutting blades 16 and 18 are separable from each other, each including apair of beveled end surfaces 38 and 40 adapted to flushly engage thecorresponding portion of the other cutting blade. Preferably, the topends of threaded fastening mmembers 20 are provided with Allen wrenchfittings, or the like, to facilitate tightening of the cutting blades tothe mounting base upon reassembly.

It will be appreciated, that the multi-piece die structure of thepresent invention provides a versatile means for repair or replacementof the curved cutting blades without the need for replacing the costlymounting base. With conventional die constructions, it was necessary toreplace the entire structure including the mounting base, such resultingin the waste of costly materials. Furthermore, due to the awkwardness ofthese conventional one-piece constructions, it was often impractical orimpossible to sharpen or repair the cutting blades. With the multi-piececonstruction of the present invention, the costly replacement of themounting base is eliminated, and the cutting blades may be easilyrepaired or replaced in a minimum amount of time. The threaded fasteningmembers 20, together with alignment dowels 32 and 34 assure a snug andproper fit between the component pieces upon reassembly.

Referring to FIGS. 3 and 4, the male die structure associated with thepresent invention may be seen in detail. The male die structure issimilar in construction to the above-described female structure and isgenerally indicated by the numeral 42 and includes a generallyrectangular rigid mounting base 44, to which are attached a pair ofcurved cutting blades 46 and 48. Mounting base 44 includes a flatmounting surface 50 defined by a pair of downwardly extending arcuateside portions 52 and 54. Mounting base 44 is further provided with aplurality of threaded mounting holes 56 adapted to receive threadedfastening members 58 which extend therethrough for engagement withthreaded apertures 59 formed in the top edge portions of cutting blades46 and 48. In addition, two pairs of alignment dowels 60 and 62 extendbetween mounting base 44 and the cutting blades to assure properalignment therebetween. Each cutting blade includes a beveled cuttingedge portion 64 which slants upwardly and inwardly, as shown in FIGS. 3and 4. The end edge of portions 66 and 68 of cutting blades 46-and 48are beveled in a manner similar to those of the female die structure, asexplained above, to assure flush engagement between the cutting blades.The assembly and disassembly of the male die structure is similar tothat of the female structure and the attributes of the female structureapply, likewise, to the male die structure.

Referring to FIG. 5, the relationship between the male and female diestructures in the mated condition may be more fully appreciated. It willbe noted that male cutting blades 46 and 48 are curved in a shapecorresponding to that of central opening 14 in the female mounting base12. The outside dimensions of the male cutting blades are such that theyare maintained in substantially flush sliding engagement with the innersurfaces of opening 14'and female cutting blades 16 and 18. Thisengagement is essential if proper cutting results are to achieved. Thisis assured by the over-all rigidity of the male and female diestructures achieved by the unique mounting arrangement of the componentpieces, as described above.

It will be appreciated from the foregoing description that themulti-piece patching die assembly of the present invention provides aconvenient means for" the repair or replacement of the die cuttingblades, yet, provides a die structure which is relatively simple inoverall construction, durable, long lasting, and relatively inexpensiveto manufacture. The patching die assembly of the present inventionresults in a substantial cost savings compared with conventional diesutilized for the same manufacturing purposes.-

The foregoing is considered as illustrative only of the principles ofthe invention, Further, since numerous modifications and changes willreadily occur to those skilled in the art, it is not desired to limitthe invention to the exact construction and operation shown anddescribed, and accordingly all suitable modifications and equivalentsmay be resorted to, falling within the scope of the invention.

What is claimed as new is as follows:

I. A die assembly comprising male and female die structures eachincluding a rigid mounting base generally rectangular in configurationand including a substantially flat mounting surface, a pair ofoppositely disposed elongated curved cutting blades removably connectedto each of said mounting bases, each of said cutting blades including anarcuate beveled edge portion defining one longitudinal edge portion anda flat mounting edge portion defining the opposite longitudinal edgeportion, said flat mounting portions normally abutting the flat mountingsurface on the corresponding mounting base, and means for selectivelyfastening said curved cutting blades to the corresponding mounting base.

2. The assembly set forth in claim 1 wherein the cutting blades of saidmale die structure include outer surfaces each having a size andconfiguration approximating those of the inner surfaces associated withthe female cutting blades such that the male cutting blades are in snugsliding engagement with said female cutting blades.

3. The assembly set forth in claim 1 wherein the fastening meansassociated with said male and female die structures each include aplurality of threaded fasteners extending between the respectivemounting bases and cutting blades to rigidly secure the cutting bladesagainst movement relative to the corresponding mounting base.

4. The assembly set forth in claim 3 wherein the cutting blades of saidmale die structure include outer surfaces each having a size andconfiguration approximating those of the inner surfaces associated withthe female cutting blades such that the male cutting blades are in snugsliding engagement with said female cutting blades.

5. The structure set forth in claim 4 wherein each of said mountingbases includes a plurality of arcuately spaced mounting holes normallyvaligned with the flat mounting edge portions of the correspondingcutting blades.

6. The assembly set forth in claim 5 wherein each of said cutting bladesincludes a plurality of mounting apertures spaced along the flatmounting edge portions thereof and being aligned with correspondingmountin holes in said mounting base.

7. The assembly set forth in claim 6 wherein said fastening meansincludes a plurality of threaded fasteners extending between saidmounting holes and said mounting apertures for rigidly securing saidcutting blades against movement relative to the corresponding mountingbase.

8. The assembly set forth in claim 7 wherein said fastening meansfurther includes a plurality of alignment dowels extending between andsnugly received by corresponding mounting holes and mounting aperturesformed in the cutting blades, respectively.

1. A die assembly comprising male and female die structures eachincluding a rigid mounting base generally rectangular in configurationand including a substantially flat mounting surface, a pair ofoppositely disposed elongated curved cutting blades removably connectedto each of said mounting bases, each of said cutting blades including anarcuate beveled edge portion defining one longitudinal edge portion anda flat mounting edge portion defining the opposite longitudinal edgeportion, said flat mounting portions normally abutting the flat mountingsurface on the corresponding mounting base, and means for selectivelyfastening said curved cutting blades to the corresponding mounting base.2. The assembly set forth in claim 1 wherein the cutting blades of saidmale die structure include outer surfaces each having a size andconfiguration approximating those of the inner surfaces associated withthe female cutting blades such that the male cutting blades are in snugsliding engagement with said female cutting blades.
 3. The assembly setforth in claim 1 wherein the fastening means associated with said maleand female die structures each include a plurality of threaded fastenersextending between the respective mounting bases and cutting blades torigidly secure the cutting blades against movement relative to thecorresponding mounting base.
 4. The assembly set forth in claim 3wherein the cutting blades of said male die structure include outersurfaces each having a size and configuration approximating those of theinner surfaces associated with the female cutting blades such that themale cutting blades are in snug sliding engagement with said femalecutting blades.
 5. The structure set forth in claim 4 wherein each ofsaid mounting bases includes a plurality of arcuately spaced mountingholes normally aligned with the flat mounting edge portions of thecorresponding cutting blades.
 6. The assembly set forth in claim 5wherein each of said cutting blades includes a plurality of mountingapertures spaced along the flat mounting edge portions thereof and beingaligned with corresponding mounting holes in said mounting base.
 7. Theassembly set forth in claim 6 wherein said fastening means includes aplurality of threaded fasteners extending between said mounting holesand said mounting apertures for rigidly securing said cutting bladesagainst movement relative to the corresponding mounting base.
 8. Theassembly set forth in claim 7 wherein said fastening means furtherincludes a plurality of alignment dowels extending between and snuglyreceived by corresponding mounting holes and mounting apertures formedin the cutting blades, respectively.